Applicant's UK Patent Specifications Nos. 2127658A and 2137860A disclose microwave ovens having a magnetron for delivering microwave power to the oven cavity and a forced hot air system for delivering a forced flow of hot air through the oven cavity. Applicant's European Patent Specification No. 0239290 discloses a development where the cooking sequence (which is controlled by a microprocessor) is dependent on values measured during cooking, so compensating for variations between individual ovens. The results obtained by this development have been satisfactory, except when cooking cakes, certain types of which tend to be over-cooked while other types tend to be under-cooked. For example, madeira cakes and cakes like Black Forest gateaux tend to be over-cooked while heavier fruit cakes tend to be under-cooked. It is thought that over-cooking occurs because these cakes are cooked in a fairly short time and are subjected to too much microwave power proportionately, whereas the heavier cakes like fruit cakes are subjected to only just enough microwave power. The invention is directed to solving this problem. The invention also takes into account variations between cake mixes, variations in ambient temperature and while compensating for a hot or warm (as distinct from cold) starting temperature.